Active winglet

ABSTRACT

An active winglet includes a body portion substantially parallel to a wing of an aircraft, as if it were an extension of the wing. The body portion is attachable to an aircraft wing and includes a controllable airflow modification device coupled thereto. By virtue of having a controllable airflow modification device, the winglet is capable of adjusting a control surface of the controllable airflow modification device in response to in-flight conditions, to reduce wing loads, increase range, and/or increase efficiency.

RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.12/797,742 entitled “Active Winglet,” filed Jun. 10, 2010, which claimsthe benefit of U.S. Provisional Patent Application No. 61/265,534entitled “Active Winglet,” filed on Dec. 1, 2009, both of which areincorporated herein by reference.

BACKGROUND

There exists an ever growing need in the aviation industry to increaseaircraft efficiencies and reduce the amount of fossil fuels consumed.Winglets have been designed and installed on many aircraft includinglarge multi-passenger aircrafts to increase efficiency, performance, andaesthetics. Such winglets usually consist of a horizontal body portionthat may attach to the end of a wing and an angled portion that mayextend perpendicularly from the horizontal body portion. For example, awinglet may be attached to a pre-existing wing of an aircraft toincrease flight efficiency, aircraft performance, or even to improve theaesthetics of the aircraft.

However, the cost to install a winglet on an aircraft is oftenprohibitive due to the requirement to engineer and certify the wingafter the wing is installed. Thus, aftermarket installation of wingletshas generally been reserved for large aircrafts owned and operated bylarge aircraft companies.

Existing winglets have limited utility, in that each winglet must bedesigned and certified for a specific wing of a specific aircraft model.Additionally, existing winglets, which are fixed, are unable to adapt tochanges in in-flight conditions. Accordingly, there remains a need inthe art for improved aircraft winglets.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description is set forth with reference to the accompanyingfigures. In the figures, the left-most digit(s) of a reference numberidentifies the figure in which the reference number first appears. Theuse of the same reference numbers in different figures indicates similaror identical items.

FIG. 1 depicts an illustrative active winglet attachable to a wing of anaircraft.

FIG. 2 depicts an illustrative aircraft with an attached active winglet.

FIG. 3 depicts the illustrative active winglet of FIG. 1 and across-sectional view of the active winglet, taken along line A-A of FIG.3.

FIG. 4 depicts an illustrative cross-section of the active winglet ofFIG. 1 with a mechanical control system.

FIG. 5 depicts an illustrative cross-section of the active winglet ofFIG. 1 with a computer controlled control system.

FIG. 6 depicts a design load comparison graph.

FIG. 7 depicts a design stress and moment load comparison graph.

FIG. 8 depicts a flowchart illustrating details of a controllableairflow modification device.

DETAILED DESCRIPTION Overview

This application describes active winglets for improving the efficiency,performance, and aesthetics of an aircraft as well as decreasing thecertification cost and time. Active winglets may include controllableairflow modification devices. By virtue of having controllable airflowmodification devices, such active winglets may be able to adjust edgesand/or portions of the control surfaces of a controllable airflowmodification device in response to in-flight load factor data and flightcondition data.

As discussed above, adding winglets to an existing wing improvesairplane efficiency and performance by reducing drag. This performancebenefit comes at the cost of adding additional stress to the wing thatwas not accounted for by the original airplane manufacturer. As aresult, installing traditional passive winglets on airplanes isexpensive because the wing must be fully analyzed, reverse engineered,and tested to determine if the wing has the structural ability toaccommodate the addition of winglets. In most cases, structural wingmodifications are required. In all cases, the useful life (fatigue life)of the wing is reduced, thereby increasing the total cost of airplaneownership to the customer. In contrast, the active winglets describedherein reduce the engineering and certification costs because activewinglets have a minimal (potentially even beneficial) structural effectwhile maintaining a positive aerodynamic effect. As previously noted, anactive winglet according to this disclosure may have an airflow controlsystem in the form of a controllable airflow modification device locatedon the winglet. This controllable airflow modification device located onthe winglet may be adjusted, which may change the aerodynamic forces onthe aircraft wing.

The active winglet on an aircraft may be designed to keep spanwisesection loads at or below originally designed values for a given wingwithout a winglet. Thus, the active winglet may eliminate therequirement to have a wing reinforced due to the addition of thewinglet. Additionally, the controllable airflow modification device ofthe active winglet may be configured to reduce the bending moment of thewing by moving the center of pressure of the wing inboard and/or reducethe impact of the winglet on the fatigue life of the wing. Therefore,the addition of the active winglet may not significantly decrease, if atall, the service life of the wing and/or the aircraft to which it isattached. In some instances, addition of an active winglet may evenreduce fatigue and increase an overall service life of the wing and/orthe aircraft to which it is attached. Additionally, in the same or otherinstances, addition of an active winglet may also increase the overallcapacity of the wing carrying capability of the aircraft, thusincreasing the aircraft's gross weight potential.

Illustrative Active Winglet

FIG. 1 depicts an illustrative active winglet 100 which may beattachable to a wing 102 of an aircraft (not shown). In one embodiment,the active winglet 100 may include a body portion 104 which may besubstantially parallel to a horizontal plane and/or a wing of anaircraft. By way of example only, and not limitation, the active winglet100 may also include an angled portion 106 on the outer side of the bodyportion 104 and an attachable portion 108 on the inner side of the bodyportion 104. In this example, the outer and inner sides of the bodyportion 104 are described with relation to the wing 102 such that theouter side is further from the wing 102 than the inner side.Additionally, the angled portion 106 may be substantially vertical inrelation to the body portion 104 such that it projects perpendicularlyfrom the body portion 104. However, in other embodiments, the angledportion 106 may be configured to project from the body portion 104 atangles other than 90 degrees. In yet other embodiments, the angledportion 106 may be configured to project from the body portion 104 atangles which include projecting downward (in relation to the aircraft).Additionally, although the angled portion 106 is described above asprojecting from the outer side of the body portion 104, the activewinglet 100 may be designed such that the angled portion 106 may projectfrom the middle, or any other location, of the body portion 104 (i.e.,the angled portion 106 may be located at any location between the innerand outer sides of the body portion 104).

The active winglet 100 may include a controllable airflow modificationdevice 110 in the form of one or more control surfaces 112 located onthe body portion 104 and/or the angled portion 106. By further way ofexample, in one embodiment, the controllable airflow modification device110 may be located on the body portion 104 of the active winglet 100. Inanother embodiment, the controllable airflow modification device 110 maybe located on the angled portion 106 of the active winglet 100. In yetanother embodiment, the controllable airflow modification device 110 maybe located on both the body portion 104 and the angled portion 106 ofthe active winglet 100. Further, and by way of example only, in theembodiment shown in FIG. 1, the controllable airflow modification device110 is shown located on the aft of the active winglet 100 (i.e., theback-side of the active winglet 100 in relation to the front of anaircraft). In this way, adjustment of the controllable airflowmodification device 110 may change the angle of the control surface 112in relation to the aft portion (body portion 104 or angled portion 106)of the active winglet 100 that the control surface 112 is located.Additionally, as shown in FIG. 1, the active winglet 100 may include twocontrollable airflow modification devices 110; however, more or lesscontrollable airflow modification devices 110 are possible.

Further, as shown in FIG. 1 by way of example only, the angled portion106 is shown as a basic trapezoidal shape. However the angled portion106 may be rectangular, triangular, oval, or any other geometric shape.Additionally, the airflow control surface 112 located on the angledportion 106, may be similar in shape to, or the same shape as, theairflow control surface 112 located on the body portion 104 of theactive winglet 100.

Additionally, the active winglet 100 in FIG. 1 illustrates, by way ofexample and not limitation, a sensor 114 located in the center of thebody portion 104 on the active winglet 100. However, the sensor 114 maybe located anywhere on the active winglet 100, for example it may belocated on the angled portion 106, on the front of the body portion 104(in relation to the aircraft), on the aft of the body portion 104 (inrelation to the aircraft), on the surface of the winglet 100, inside thewinglet 100 (i.e., located within the surface of the winglet 100),anywhere within the entire aircraft, or the like.

Also depicted in FIG. 1, by way of example only, is an illustrative wing102 of an aircraft (not shown) prior to the attachment of an activewinglet 100 as described above. The wing 102 may include an aileron 116and a flap 118. The aileron 116 and the flap 118 are used for flightcontrol of the aircraft and in some instances may be controlled by oneor more pilots of the aircraft.

FIG. 1 also depicts the illustrative modified wing 120 which may includethe illustrative wing 102 coupled to the active winglet 100. Themodified wing 120 may be designed and crafted for a new aircraft, or theactive winglet 100 may be attached to the existing wing 102. The activewinglet 100 of modified wing 120 may be configured in a similar shape asthe existing wing 102. Additionally, and by way of example only, thewinglet 100 may fit over a portion of the existing wing 102 such thatthe end of the existing wing 102 resides within the attachable portion108 of the active winglet 100. In other embodiments, however, the activewinglet 100 may be attached to the existing wing 102 by fastening theend of the existing wing 102 to the attachable portion 108. Further, thewinglet 100 may be fabricated of the same or similar material as theexisting wing 102.

Illustrative Aircraft with Active Winglet

FIG. 2 depicts an illustrative load alleviation system 200 implementedon an aircraft 202 that includes at least one attached active winglet100. The components of the load alleviation system 200 may includesensors 114, active winglet(s) 100, a control system 204, and controlsurface(s) 112. By way of example only, and not limitation, FIG. 2illustrates one active winglet 100 on each wing of the aircraft 202.However, active winglets 100 may also be placed on other surfaces of theaircraft 202. For example, the active winglets 100 may be located on thewings, as shown, or they may be located on the tail wings, or any otherhorizontal or vertical surface of the aircraft 202.

As mentioned above, the load alleviation system may comprise a controlsystem 204. The control system 202 may be configured to control theactive winglets 100 of the aircraft 202. By way of example only, and notlimitation, the control system 204 may include one or more processor(s)206 for receiving and processing system data, including, but not limitedto, in-flight load factor data. In one embodiment, the processor(s) 206may receive in-flight data from the sensors 114. As mentioned above withrespect to FIG. 1, although the sensors 114 are shown on the wing theymay be located anywhere on the aircraft. The control system 204 mayadditionally consist of memory 208 for the storage of in-flight loadfactor data. The data stored in the memory 208 may include previouslyreceived load factor data, currently recorded (i.e., current in-flight)load factor data, or a compilation of current in-flight data and/orpreviously recorded in-flight data. By way of example only, the memory208 of the control system 204 may include an operating system 210 andcontrol logic 212.

The operating system 210 may be responsible operating the control system204 by way of interfacing the data with the processor(s) 206 andproviding a graphical user interface (not shown) for interaction withone or more pilots of the aircraft 202. The control logic 212 of thecontrol system 204 may be configured to operate the control surface(s)112 of the controllable airflow modification devices 110 of the activewinglet 100. In one embodiment, the control logic 212 may control thecontrol surface(s) 112 based on in-flight load factor data received fromthe sensor(s) 114. Additionally, although not shown here, predeterminedparameters may be stored in the memory 206. The predetermined parametersmay also be used by the control logic 212 to determine operation of thecontrol surface(s) 112. In some embodiments, the control system 204 mayoperate each control surface 112 simultaneously or independently. By wayof example only, the control system 204 of FIG. 2 is illustrated in thehull of the aircraft 202; however, it can be located anywhere on theaircraft, including, but not limited to, the cockpit, the tail, thewing, or the like.

Illustrative Airflow Modification Devices

FIG. 3 depicts the active winglet 100 of FIGS. 1 and 2 and includes across-sectional view 300 of the active winglet 100, taken along lineA-A. The cross-section 300 runs across the body portion 104 of thewinglet 100. Additionally, the cross-section 300 of the body portion 104of the winglet 100 illustrates one embodiment of the components of thecontrol system 204 of FIG. 2 located in the active winglet 100. As shownin FIG. 3, the control system 204 may be located in the body portion 104of the winglet 100; however, the control system 204 may be located inthe angled portion 106 of FIG. 1 of the winglet 100, in other portionsof the active winglet 100, or in any location on the aircraft.

In one embodiment, by way of example only, the control system 204 may becommunicatively and/or mechanically coupled to the control surface 112by way of a connection 302. FIG. 3 illustrates the connection 302 as onesubstantially straight coupling from the control system 204 to thecontrol surface 112. However, the connection 302 may bend, turn, pivot,or be a series of multiple connections to make the connection 304. Theconnection 304 between the control system 202 and the control surface112 may be operable by electronic, mechanic, or any other resource forcoupling the control surface 112 to the control system 204. The controlsurface 112 may be coupled to the active winglet 100 by a hinge, pivot,or other swivel device 304 to allow the control surface 112 to rotatethe aft end up and/or down in relation to the body of the active winglet100. As noted above, to the commands given by the control system 204 tooperate the control surface 112 of the active winglet may be based onthe load factor data received by the control system 204 from the sensors114 on the aircraft 202.

FIG. 4 illustrates one embodiment 400 of the control system 204 as seenthrough the cross-section 300 of active winglet 100. As discussed withreference to FIGS. 2 and 3, the control system 204 may control thecontrol surface 112 of the active winglet 100 based on in-flight loadfactor data. The control system 204 may be coupled to the controlsurface 112 which may be illustrative of the airflow modification device110 illustrated in FIG. 1. The control surface 112 may be coupled to theactive winglet 100 by a hinge, pivot, or other swivel device 304 toallow the control surface 112 to move in relation to the commands givenby the control system 204.

Additionally, by way of example only, FIG. 4 depicts an illustrativeembodiment of a mechanical control system 402. The mechanical controlsystem 402 may include of a bob weight 404 coupled to a spring 406. Thebob weight 404 may be fabricated of lead, or any other weight which mayactivate the mechanical control system 402. The spring 406 may be madeof coil springs, bow springs, or any other device used to createresistance for the bob weight 404. In one embodiment, and by way ofexample only, the bob weight 404 may be coupled to the control surface112 by way of a coupling system 408. By way of example only, couplingsystem 408 may be a rigid object, belt, chain, or other resource forcoupling the bob weight 404 to the control surface 112. The couplingsystem 408 is illustrated by way of example only, with two pivot points410 and 412, and one fixed point 414. The coupling system 408 may alsocontain a series of pivot points, angles, or other connections. Thecoupling system 408 may be configured to connect to spring 406 at thefixed point 414.

In one embodiment, the mechanical system 402 may be configured to reactto in-flight conditions, for example, a gust of wind, maneuvers producedby one or more pilots, or any other condition on the wing of theaircraft. Based on the in-flight conditions, the bob weight 404 maychange position within the mechanical system 402 relative to the spring.For example, the bob weight 404 may drop, lift, or otherwise changelocation, depending on the in-flight conditions. When the bob weight 404changes location, it may cause the coupling system 408 to initiate aresistance force on the spring 406 causing a counter weight 416 to movein the opposite direction. Consequently, motion of the counter weight416 may adjust the two pivot points 410 and 412 such that the couplingsystem 408 causes the connection 306 to adjust the control surface 112.

FIG. 5 illustrates an additional embodiment 500 of a logical controller502 as seen through the cross-section 300 of active winglet 100. Asdiscussed with reference to FIGS. 2-4, the logical controller 502, muchlike the control system 204 of FIG. 4, may control the control surface112 of the active winglet 100 based on in-flight load factor data. Byway of example, and not limitation, the embodiment 500 of FIG. 5 mayinclude one or more sensors 114, a logical controller 502, and a motor504. The sensors 114 may be representative of the sensors illustrated inFIG. 1. The sensors 114 may be electronically coupled to the logicalcontroller 502. The logic controller 502 may be coupled to the motor504. The motor 504, by way of example only, may be an electric motor. Inone example, the motor 504 may be coupled to the control surface 112.The motor 504 may be able to rotate the aft portion of the controlsurface 112 up or down, depending on the received in-flight conditionsand the predetermined load factors programmed into the logicalcontroller 502. Additionally, the motor 504 may be coupled to thecontrol surface 112 by way of electronic, pneumatic, hydraulic, oranother resource for actuating the control surface 112. In at least oneembodiment, and by way of example only, the motor 504 may cause thecontrol surface 112 to pivot on an axis, moving the aft portion up andor down to adjust the control surface 112 as calculated by the logicalcontroller 502.

The logical controller 502 may be located in the active winglet 100, thecockpit (not shown), the main fuselage of the aircraft (not shown), oranywhere located on the aircraft. In-flight load factor data may befirst received by the sensors 114 located on the aircraft 202. Theinformation may be resulting from deliberate in-flight maneuvers by apilot, gusts of wind, or other causes of change in conditions to theaircraft. Information gathered by the sensors 114 may be received by thelogical controller 502 and the data may be analyzed or otherwiseprocessed. In one example, the logical controller 502 may be programmedwith predetermined load factors which may be representative of aspecific make and model of the aircraft. Additionally, the logicalcontroller 502 may calculate the position of the control surface 112based on the in-flight conditions to minimize the moment load on thewing. In other words, the logical controller 502 may receive thein-flight conditions and determine the needed position of the controlsurface 112. Additionally, the logic controller 502, may send a signalto the motor 504 to which it may be coupled to effectuate control of thecontrol surface 112. By way of example only, the motor 504 may beelectronic, pneumatic, hydraulic, or any other type of motor.

Illustrative Comparison Graphs

FIG. 6 illustrates a graph 600 which compares the load factor on a wingof an aircraft in relation to the location on the wing of the aircraft.The wing of FIG. 6 is a general representation of a wing and is not maderepresentative of a specific make or model of an aircraft wing. TheX-axis of the graph is illustrative of the location on the wing. It isrepresented in percentage (%) of the semi-span of the wing. The lengthof the wing is only a representation and is not limiting of the size ofthe wing on which an active winglet 100 may be installed. The Y-axis isrepresentative of the lift distribution on the wing. The load is higherthe closer to the center of the airplane. The graph 600 is forillustrative purposes only, and illustrates one example of the loaddistribution which an aircraft may experience. The graph 600 is notrestrictive of whether or not the distributed load may be more or lessat any point on the graph. The graph 600 is representative of the basicshape of the distributed load a wing may encounter.

The graph 600 illustrates the lift distribution on a traditionalmanufactured wing, which is represented by the line on the graph 600with a dash and two dots. The graph 600 also illustrates the liftdistribution on the wing when a traditional winglet is installed, whichis represented by the dashed line. Additionally, the graph 600illustrates the lift distribution on the wing when an active winglet 100is incorporated on the wing. The comparison illustrates that the liftdistribution caused by the traditional winglet may be greater at thewingtip. This may move the center of lift of the wing outboard which mayincrease the wing bending loads. However, when the wing has an activewinglet 100 utilizing the load alleviation active winglet system 200 thelift distribution at the wing tip may drop significantly lower than thatof a traditional winglet. The graph 600 illustrates that the load mayeven drop below zero at the location of the wing tip (the point furthestaway from the aircraft). These loads are representative of the designload on the aircraft, which is the highest load an aircraft may see.When the active winglet controllable surfaces 112 are undeployed, theactive winglet 100 produces the same efficiency benefits of a passive orfixed winglet. When the load factor increases and the loads on the wingincrease, the control surfaces 112 on the winglet 100 may adjust toreduce the loads on the wing. In one embodiment, the active wingletcontrol surfaces 112 may be undeployed or undeflected the majority ofthe time. However, in another embodiment, they may only be deployed whenthe load on the wing approaches the original design loads.

FIG. 7 illustrates a graph 700 representing a wing design stresscomparison of active winglet systems, a wing with a winglet with noactive system, and a standard wing. The design stress or design load isthe critical load to which the wing structure is designed to carry. TheX-axis represents the location along the length of an aircraft's wing.The unit is shown in percentage (%) of wing semi-span. The length of thewing is only a representation and is not limiting of the size of thewing on which an active winglet 100 may be installed. Additionally, inFIG. 7, the Y-axis represents the load on the wing. This load isillustrative of the design root bending moment load. The comparisonshows the standard load that the wing bears. The graph 700 is forillustrative purposes only and is not meant to be restrictive in anyway. The root bending moment load may be greater or smaller for varyingwing makes and models. The graph 700 also shows the load of a wing whena winglet is added with no active systems. The graph 700 additionallyshows the loads on the wing when a winglet is added to the wing.

With the active winglet system 200 enabled on the winglet 100 the designmoment loads may be lower than the design loads on the wing with awinglet with no active system. Additionally, with the active system 200enabled on the winglet 100, the moment loads may be lower than the loadson the wings with no winglets installed. Traditional winglets increasewing stress, as a function of load factor, and substantially reduce thefatigue life of the wing. The slope of the “stress per g” curve isnormally linear and the addition of passive winglets increases the slopewhich reduces the expected life and calculated life of the wing. Activewinglets reduce the slope of this curve so that it is the same or lowerthan the slope of the original curve.

Illustrative Methods

FIG. 8 illustrates a flow diagram of one method 800 of receiving data,calculating, and positioning the control surface. As discussed above thesensors receive data based on the flight conditions of the aircraft. Themethod may, but not necessarily, be implemented by using sensors 112shown in FIG. 1. In this particular implementation, the method 800begins at block 802 in which the method 900 receives data from thesensors located on the aircraft. At block 804 the signal is received andcomputed with pre-registered data programmed into the adjustable controldevice. The adjustable control device in block 804 sends a signal, basedon the calculation, to block the control surface 806. At block 806 thecontrol surface receives the signal and may be adjusted up or down basedon its hinge point, depending on the signal received from the adjustablecontrol device.

CONCLUSION

Although embodiments have been described in language specific tostructural features and/or methodological acts, it is to be understoodthat the disclosure is not necessarily limited to the specific featuresor acts described. Rather, the specific features and acts are disclosedas illustrative forms of implementing the embodiments.

1. An aircraft comprising: a fuselage; a baseline wing, the baselinewing coupled to the fuselage at a first end of the baseline wing andhaving an aileron; and a winglet comprising: a horizontal portioncoupled to a second end of the baseline wing, such that the horizontalportion is outboard of the baseline wing; and a controllable airflowmodification device directly coupled to the horizontal portion of thewinglet.
 2. The aircraft of claim 1, the controllable airflowmodification device, comprising: a control surface disposed at atrailing edge of the baseline wing, such that the control surface issubstantially parallel to the baseline wing; and a control system forcontrolling motion of the control surface based at least in part onin-flight load data.
 3. The aircraft of claim 1, the control surfacebeing specifically configured for the aircraft based at least in part onflight data.
 4. The aircraft of claim 1, the control surface beingadjustable electronically, mechanically, hydraulically, and/orpneumatically.
 5. The aircraft of claim 1, the control system beingcommunicatively coupled to a sensor located on the aircraft andconfigured to receive a signal from the sensor located on the aircraft.6. A winglet fixedly attachable to a baseline wing of an aircraft, thewinglet comprising: a horizontal portion that is substantially parallelto the baseline wing of the aircraft, the horizontal portion beingconfigured to fixedly attach to an outboard portion of the baseline wingof the aircraft; and a controllable airflow modification device directlycoupled to the horizontal portion of the winglet.
 7. The winglet ofclaim 6, the controllable airflow modification device being coupled tothe trailing edge of the horizontal portion of the winglet.
 8. Thewinglet of claim 6, the horizontal portion being configured to fixedlyattach outboard of an aileron and/or a flap of the baseline wing of theaircraft.
 9. The winglet of claim 6, at least one of the horizontalportion or the controllable airflow modification device beingspecifically configured for a specific aircraft.
 10. The winglet ofclaim 9, the controllable airflow modification device being specificallyconfigured for the specific aircraft based at least in part on flightdata of the specific aircraft.
 11. The winglet of claim 6, thecontrollable airflow modification device being configured to adjust acontrol surface of the winglet electronically, mechanically,hydraulically, and/or pneumatically.
 12. The winglet of claim 6, thecontrollable airflow modification device being coupled to a controlsystem for controlling a control surface of the airflow modificationdevice.
 13. The winglet of claim 12, the control system comprising acontrol device with control logic, the control device beingcommunicatively coupled to a sensor located on the aircraft.
 14. Thewinglet of claim 13, the control device being configured to receive asignal from the sensor located on the aircraft to indicate in-flightload factors and/or flight conditions of the aircraft.
 15. The wingletof claim 14, the control device being further configured to adjust thecontrollable airflow modification device at least partly based on thesignal from the sensor located on the aircraft.
 16. The winglet of claim6, further comprising an angled portion projecting upward at an anglefrom horizontal portion.
 17. A method comprising: receiving in-flightload factor data from a sensor located on an aircraft; and adjusting acontrollable airflow modification device located on a winglet of theaircraft based at least in part on the received in-flight load factordata, the controllable airflow modification device located on ahorizontal portion of the winglet that is substantially parallel to awing of the aircraft.
 18. The method of claim 17, the controllableairflow modification device comprising one edge or portion of a controlsurface coupled to a hinge.
 19. The method of claim 17, the adjusting ofthe controllable airflow modification device comprising rotating thecontrol surface at the hinge along a horizontal axis such that an edgeof the control surface other than the one edge coupled to the hingemoves up or down in relation to the horizontal portion of the aircraft.20. The method of claim 17, the adjusting of the controllable airflowmodification device configured to reduce a wing load of a wing of theaircraft by moving a center of pressure of the wing inboard and/orreduce an impact of a winglet on a fatigue life of a wing of theaircraft, the wing load comprising a bending moment and/or a torsionmoment of the wing.